Science & Mathematics - 27 November 2006

A student prepares a solution by dissolving 3.81 g of NaOH in enough water to make 300. mL of solution.
The student then transfers 25.0 mL of this solution into a 100. mL volumetric flask. Water is then added
up to the 100. mL mark.
What is the final molarity of NaOH in the 100. mL flask ?


Enter a numeric answer only, don't include units in your answer.

2006-11-27 15:28:00 · 2 answers · asked by nietzsche 1 in Chemistry

2006-11-27 15:27:59 · 5 answers · asked by Anonymous in Chemistry

i know that the answer is -4a^5b^7, but how do i get it

2006-11-27 15:27:28 · 1 answers · asked by sexywexy18 1 in Mathematics

I have a lab and its on comparing prokaryotes and eukaryotes, we have three stains DNA Iodine and Janus Green. Our teacher said omething about using these stains to figure oout whether the cells are gram positive or negative i just need to know what that means Help!

2006-11-27 15:27:22 · 4 answers · asked by Nizzy 1 in Biology

Which of the following statements are true?


For statements a) through d) use the reaction:


SiCl4(l) + 2Mg(s) --> 2MgCl2(s) + Si(s)



a) Mg is the reducing agent

b) SiCl4 is the reducing agent

c) Mg is reduced

d) SiCl4 (or Si in SiCl4) is reduced

e) CH4(g) + 2O2(g) --> CO2(g) + 2H2O(g) is a redox reaction

f) Al(OH)4-(aq) --> AlO2-(aq) + 2H2O(l) is a redox reaction

Note: you can have more than one answer.

2006-11-27 15:26:03 · 3 answers · asked by nietzsche 1 in Chemistry

Go back to the Past or experience the Future?

2006-11-27 15:24:47 · 6 answers · asked by simplyJESSE 2 in Engineering

2006-11-27 15:24:43 · 7 answers · asked by Anonymous in Biology

2006-11-27 15:24:35 · 2 answers · asked by mini 1 in Biology

I can see why a rocket would need to fly fast in order to stay in orbit. But that's not the question; in such a case the rocket would balance the gravitational pull and not escape it.

If a rocket would fly, somehow, at a constant 1 m/s, wouldn't it (eventually) leave our solar system ?

2006-11-27 15:24:16 · 9 answers · asked by Anonymous in Astronomy & Space

2006-11-27 15:21:55 · 18 answers · asked by Samantha L 1 in Weather

Entropy is the
measure of the disorder
in a system. When energy
transforms from one form to
another, it goes toward greater
disorder, therefore greater entropy!

What does all of that mean? Does it mean that things have a natural drive to get messy? Or that entropy increases as enegy transforms such as the enegy of the sun is absorbed by trees and the trees produce oxygen and that is absorebed by humans and humans produce CO^2 and so on? Would that cycle constitute as increasing entropy?

CAn someone explain?

2006-11-27 15:18:29 · 8 answers · asked by whosit? 2 in Chemistry

They're caused by hot tyres, but what *are* they actually? Rubber tyre molecules (whatever compounds they're made of)? How are they formed? Can someone describe the process in detail?

I also want to know if the marks can be removed, and how?

2006-11-27 15:18:28 · 2 answers · asked by espers_cypher 2 in Chemistry

x(t)=3t-2 y(t)=t+2

2006-11-27 15:17:59 · 2 answers · asked by Anonymous in Mathematics

I need help figuring out how to solve this. (x+1)^3
I know the answer is not (x+1)*(x+1)*(x+1)... There's a special formula to solve this, though I've forgotten it.

Thanks!

2006-11-27 15:17:58 · 9 answers · asked by Cappy 1 in Mathematics

I need to know whether the following disorders are autosomal or sexlinked AND if theyre dominant or recessive:

Alzheimer's
Fragile X
Phenylketonuria (PKU)
Turner syndrome

Autism
Werner's syndrome
Hemophilia
Polycystic kidney disease

Any help would be great, so if you don't know them all please help with whatever you can :)

2006-11-27 15:14:49 · 2 answers · asked by smokefanTS20 3 in Biology

2006-11-27 15:13:52 · 2 answers · asked by LUIS A 1 in Weather

I am buying my 12 year old son a telescope for Christmas.

It seems that the telescopes that automatically point to celestial objects would be the best option... or am I wrong, and why?

Do they work? Why do they offer telescopes without this feature?

The two I am looking at are the:

Meade NGC-70TCR Telescope for $200

http://shopping.discovery.com/product-57684.html

or the Celestron® StarSeeker™ 80mm GoTo Refractor Telescope for $329.

http://www.telescope.com/shopping/product/detailmain.jsp?itemID=257599&itemType=PRODUCT&iMainCat=0&iSubCat=0&iProductID=257599

Both have the star finder computer on board and look cool.

Any thoughts/recommendations?

Thank you!

2006-11-27 15:13:33 · 6 answers · asked by Genie♥Angel 5 in Astronomy & Space

2006-11-27 15:11:18 · 7 answers · asked by taaxi1111 1 in Physics

2006-11-27 15:10:15 · 4 answers · asked by princess220102 1 in Geography

i'm trying to evaluate the trigonometric function of the quadrant angle sec(pie). i really just dont understand this whole concept of using reference angles and such. can anyone please show me how to do this problem and explain how it is done. please help as i have a quiz on this stuff tomorrow and i really just dont understand. i would be extremely grateful :). thanx!

2006-11-27 15:09:55 · 2 answers · asked by Simply Me 1 in Mathematics

2006-11-27 15:05:23 · 2 answers · asked by Anonymous in Mathematics

2006-11-27 15:05:06 · 3 answers · asked by oznerol_57 1 in Earth Sciences & Geology

2006-11-27 15:03:57 · 2 answers · asked by spmdusa 1 in Engineering

When you buy a 16 oz. bad of chips, you expect to get precisely 16 ounces. the actual wieght W(in ounces) of a 16 oz bag of chips is given by Iw-16I< or equal to 1/2. You buy four 16 oz bags. What is the greatest amount you can expect to get? What is the smallest amount? Explain.

2006-11-27 15:03:06 · 1 answers · asked by William M 2 in Mathematics

(a) Estimate the area under the graph of f(x) = 25 - x^2 from x = 0 to x = 5 using five approximating rectangles and right endpoints.
b) Estimate the area using left endpoints.

2006-11-27 15:00:44 · 4 answers · asked by Anonymous in Mathematics

write a skelton equation with the corrected formula for each chemical in the reaction.

2006-11-27 15:00:14 · 2 answers · asked by carboy_carlover 1 in Chemistry

2006-11-27 14:58:57 · 7 answers · asked by Joan V 1 in Chemistry

I cant seem to isolate a variable to get an answer please someone help me go thru this

x-2y+3z=7
2x+y+5z=17
3x-4y-2z=1

2006-11-27 14:58:18 · 4 answers · asked by Anonymous in Mathematics

2006-11-27 14:56:39 · 4 answers · asked by Samantha L 1 in Medicine

i will try

2006-11-27 14:55:49 · 1 answers · asked by Anonymous in Engineering